IIBRIRY OF CO?^^GRESS. 

OITED SIAIES OF AMEKICA. 



/ '■' 



THE 

TEEE-LIFTEE ; 

OR, 

A NEW METHOD OF TRANSPLANTING 
FOREST TREES. 



BY 



COLONEL GEORGE 6REEW00D. 



HE WHO HAS PLANTED A TREE HAS SET THE ELEMENTS TO WORK 
FOR, HIM. 



LONDON: 

PRINTED FOR 

LONGMAN, BROWN, GREEN, AND LONGMANS, 

PATERNOSTER-ROW. 
1844. 



/ ^ xj London: 
- Printed l»y A. Spottiswoode, 

* New- Street- Square. 



THE 



TREE-LIFTEK. 



INTRODUCTORY. 

Among the advantages of transplanting 
with the " Tree-lifter" may be reckoned 
its cheapness. Its simplicity is such that 
the whole may be performed, and even 
single-handed, by a common day labourer. 
One man may plant one tree per day, of 
from twenty-five to thirty feet in height. 
To transplant trees without the ball of 
earth requires great care, labour, and 
expense in tracing out the small fibres 
of the roots, which after all are nearly 
valueless. All transplanted trees are the 
better for being watered ; but with the 
ball of earth this is by no means neces- 

A 2 



4 

sarj. To transplant without the ball of 

earthj and not to water, for at least two 
summers, is hopeless. This is a great 
expense, besides staking, and tying, 
which plants with the ball of earth do 
not need. The growth of trees trans- 
planted with a ball of earth is not checked ; 
but without a ball of earth, trees trans- 
planted with whatever care, or at whatever 
expense, are checked in their growth for 
eight or ten years, and if they do not die, 
they become living scarecrows. 

Over the nursery plant, as a single 
tree, the transplanted tree has the advan- 
tage of a start of from twenty-five to 
thirty years, besides saving the expense 
of the material, and carpenters work, for 
at least two fences for each tree. 

The system recommended would have 
peculiar advantages for planting avenues^ 



5 



DESCRIFTION OF THE TREE-LIFTER. 

A pair of wheels eight feet in diameter, 
standing four feet six inches apart, or the 
same width apart as the common carts 
and waggons of the country. Twenty 
spokes. Width of the tire, two inches 
one eighth. The wheels quite straight, 
and undished. An iron axle of three 
inches diameter throughout, and perfectly 
straight. An iron wheel, fixed with a 
linch pin, on each end of the axle, 
outside the box of each wooden wheel. 
The iron wheels to have six spokes, 
ending in wooden handles projecting one 
foot beyond the rims. One wooden 
handle fixed on the rims between each 
spoke. The ends of these twelve handles 
to be just within the rims of the wooden 
wheels. The entire machine thus forming 
simply a windlass on wheels. A strong 
A 3 



6 



iron ring playing loose on the axle, 
and a strong iron hook playing loose 
on this ring, to hold the weight when 
raised. 

Shafts ten feet four inches from the axle ; 
to take on and off the axle by means of a 
hook and screw. Five chains twelve feet 
six inches in length, with a hook at each 
end ; one chain fourteen feet six inches in 
length, with a hook at each end, and with 
six round links at each end, to distinguish 
it from the other chains. A box with six 
compartments to hold the chains. Two 
strong planks eight feet in length, with 
a hole bored in each, to fit on to a pin 
on the shafts, along which, and across the 
axle, the planks are to rest when carried 
on the machine. A box or thill on the 
shafts to carry four blocks for the wheels, 
spades, pickaxes, &c. A South American 
surcingle, and three or four rope traces 
with a hook at each end. A strong rope 



7 

to be attached by one end to the axle. 

At the other end a strong iron 
ring to receive the chains which 
encircle the ball of earth, and to 

Obe attached to the hook and 
ring on the axle, when the 
weight is raised. 

DESCRIPTION OF THE PRUNING SAW, AND 
PRUNING LADDER. 

The best instrument to prune trees 
with is a carpenter's turning saw, with 
coarse teeth, set wide for the purpose. 
Having a large handle, with a hook to 
attach it to boughs or the rounds of a 
ladder, and admitting of the blade being 
taken in and out by screws, and replaced 
when broken. The saw is held by the 
round part of the handle while sawing a 
branch from below upward ; and all 
branches should, if possible, be begun 

A 4 



8 



from belowj to avoid tearing the bark 
and last layers of wood as the branch 
falls. A chopping instrument, such as a 
bill-hook, besides bruising and splitting 
the wood, is apt to cut too close, or not 
close enough. In the first case, the parts 
are injured from which the new healing 
growth is to proceed ; in the second 
case, a dead stump is left to be enclosed 
by the annually increasing stem, which is 
probably rotten before it is enclosed. 
Besides, a chopping instrument is not 
adapted to getting between branches to 
thin them out. These saws will pass 
between branches which are too close 
better even than the knife. One of 
these blades fixed on a light rod is the 
best instrument to clear leaders which 
cannot be reached with a knife or a hand- 
saw. In this case, work the saw in a line 
with the stem of the tree ; not across it. 
These saws may be bought at Coleman's, 
cutler, Haymarket. 



9 



The priming ladder should be triangu- 
lar ; that is, to the Kentish fruit ladder, 
wide at the base and narrow at the 
top, should be added a single prop. The 
lower end of the prop should diverge 
into two branches, to receive a wheel 
like that of a wheel-barrow. When low- 
ered, the ladder is placed and wheeled 
on this prop. When reared, the prop 
being attached to the ladder by a rope, 
it is pulled towards you by raising 
the ladder by one of its lower rounds. 
If well made this ladder is perfectly 
wieldable, and safe at the height of up- 
wards of twenty feet. The ladder is 
easily detached from the prop, and used 
singly, if required. 

DESCRIPTION OF WATER-CASK. 

I have found the following sort of water- 
cask very useful : 

A pair of old gig wheels, four feet 



10 



in diameter. A thirty-six gallon cask, 
thirty-two inches high. Swing this cask 
between the wheels by two iron arms, 
fifteen inches of the cask above the arms, 
seventeen inches below them. 

An iron handle to pass over the top of 
the cask, and sufficiently free from the 
cask to allow of its being tilted. The 
. handle to take on and off the axle with 
a hook and screw. 

A pair of old gig shafts to take on and 
off the handle. 

A leathern hose, with wire inside, at the 
lower part of the cask, just long enough, 
when turned over the cask, to reach the 
bottom of it on the other side. The 
hose to take on and off with a screw. A 
lid, opening with folding flaps, fastened 
by a bent hasp, which will pass over 
and secure the hose while in movement. 
A couple of leathern buckets. A hook 
before and behind the cask, to carry the 
buckets. 



11 



A wrought-iron bowl, to lade with. 

This cask may be used either by hand, 
or with a horse, or donkey. It may be 
locked going down hill, as recommended 
for the " tree-lifter." 

According to circumstances, or the 
power of approaching the tree, the hose or 
the buckets may be used, or the cask may 
be tilted. 

PRACTICAL PART OF TRANSPLANTING. 

Choose a tree of from twenty to thirty 
feet in height, with several leaders, or with 
some unduly large branches. Prune the 
tree previously to digging round it, so as 
to take from the head at least as much as 
will, in all probability, be taken from the 
root, not by cutting in the head and 
branches of the tree, but by giving it a 
clear leader, and cutting out all branches 
large enough to compete with the stem, 



12 



low enough to be reached by cattle, or the 
growth of which is vertical, or parallel to 
the stem. Cut all close to the stem. Dig 
a trench round the tree, at the distance of 
about twenty inches from it. Undermine 
the ball of earth, at the depth of about 
three feet, so that every root may be cut 
previous to lifting it. Tie some old car- 
peting or matting round the stem of the 
tree. Place the machine, without the shafts, 
on the planks, and block the wheels ; the 
centre of the axle over the centre of the 
ball of earth, and the ring of the windlass 
rope at the foot of the tree. Place the 
chain with the round links horizontally, 
and loosely, round the lower part of the 
ball of earth. Cross the end held in the 
left hand twice over the end held in the 
right hand, and lay both ends down. Pass 
one of the other chains, as far as its middle, 
through the ring of the windlass rope. 
Pass the ends of this chain beneath the 
horizontal chain, and hook the ends back 



13 



on the chain itself. Do the same with the 
four remaining chains. So that when the 
windlass is worked these five vertical 
chains, being at equal distances from each 
other, shall bear an equal distress from the 
weight of the ball. Fasten the horizontal 
chain, by hooking it to any convenient 
part of the vertical chains. Raise the ball 
of earth with the windlass, and place the 
ring of the windlass rope on the hook 
attached to the axle. The ball of earth 
carried thus is pressed together by the 
chains acting towards one another, and 
the greater the weight the greater the 
inward pressure. A ball of earth resting 
on a sledge or truck soon shakes to pieces 
on the least movement, besides the diffi- 
culty and mischief done in lifting it on 
and off* the truck. 

The tree is lowered into the pit pre- 
pared for it with the same facility as it 
is raised. If it does not stand upright 
it is easily raised by the windlass, while 



14 



earth is cast under where it is wanted. 
The unchaining is only reversing the en- 
chaining. If during the carriage, owing 
to wet or the friability of the earth, the 
chains cut into the ball, and the load sinks, 
it is easy, by letting the load down alto- 
gether, to take up and tighten any one or 
every one of the chains. 

Place the upper surface of the ball of 
earth at precisely its former level, and do 
not cover it ; but raise a ridge of earth 
round the outside of its circumference, so 
as to form a pan or irrigation cup. Tie 
some bushes round the stem to prevent 
cattle from rubbing it. The organisation 
of the bark is easily destroyed by any 
bruise, or by cattle rubbing against it. It 
is the common error to believe that the 
bark is poisoned by the oil from the skin 
of cattle. 

It may be found necessary to stay the 
sway of the tree while in movement, by 
ropes from the stem to the shafts. 



15 



In going down steep hills the machine 
may be held back by a horse ridden behind, 
and hooked on by the South American 
surcingle and single trace ; or the machine 
may be very conveniently blocked by 
lashing a bar of wood across the shafts, 
close in front of the wheels, and taking out 
the screw which fastens the shafts to the 
axle. The horse will then bear back 
against the wheels instead of against the 
axle, and the friction against the wheels 
will increase or decrease directly as the 
downward impetus. 

The principle of locking two-wheeled 
carriages by creating friction on the wheels 
induces a slight downward pressure on 
the horse's back. But the long shafts act 
as a lever in the horse's favour, and the 
extra pressure on his back is not to be 
spoken of in comparison with the labour 
of bearing back a loaded cart. 



16 



THEORY OF TRANSPLANTING. OUTLINE OF 
THE PHYSIOLOGY OF TREES AS REGARDS 
TRANSPLANTING, PRUNING, &C. 

The supply must be equal to the de- 
mand; if not, scarcity will ensue. He 
who expects that a diminished root will 
support an undiminished head will be 
disappointed. This is the fundamental 
principle of transplanting. And in trans- 
planting, the head must be curtailed 
exactly in proportion as you expect to 
curtail the root. 

With the exception stated below, trees 
imbibe from every part of them which is 
exposed to moisture, and give off (trans- 
pire) from every part of them wdiich is 
exposed to drought. The root is the part 
which is constantly exposed to moisture, 
and which furnishes the constant supply of 
sap to the tree. That part of the root 
which is universally believed to imbibe 



17 



no moisture, the woody part, is the only 
part which does imbibe moisture ; and 
that part of the root which is univer- 
sally believed to be the only part which 
does imbibe moisture, the unripe ends or 
fibres, is the only part which does not 
imbibe moisture. 

That trees imbibe from any part which 
is exposed to moisture is evident from the 
growth of cuttings, which have no root, 
old or young. 

In the hot climate and on the arid hill- 
sides of Spain the olive is propagated by 
cuttings. These cuttings are old branches 
seven feet in length. One end of such a 
cutting is buried about eighteen inches in 
a pit, and concrete earth or clay is raised, 
like a pillar, around it, so that, at the 
upper end, only about eight or ten 
inches of the cutting is exposed to the 
atmosphere. Thus excretion of mois- 
ture is prevented, and secretion of mois- 
ture takes place, throughout about six 

B 



18 



feet of the cutting. In tlie course of 
two or three years the pillar of earth is 
gradually taken away ; when a head has 
grown on a trunk five or six feet from 
the ground. 

Most plants which will strike from cut- 
tings will grow whether the proper end of 
the cutting is placed upwards or down- 
wards. Some plants will grow if the 
head is placed in the earth, and the roots 
in the air. In this case, the former head 
throws out roots as a cutting does, and 
the former root throws out branches as 
roots often do suckers. It is an error to 
suppose that the old organisation either 
of the actually existing head or root can 
change ; though the new growth in diameter 
of both will doubtless be reversed ; and in 
process of time the old roots should be 
encased in stem wood, and the old head in 
root wood. The internal structure of such 
a plant would be worth examination. 

If the centre parts of slips of currant 



19 



bushes are placed in the earth with both 
ends out they will absorb moisture, strike 
root, and grow. If a long vine branch is 
coiled round the inside of a flower pot, 
and covered with earth, as it is ten times 
as long below the earth as a common cut- 
ting, it will shoot with ten times as much 
vigour ; and if heat is given, it will bear 
fruit the first year. I attribute this to its 
greater quantity of wood exposed to mois- 
ture, and its consequent greater power of 
absorption ; though it may be attributed 
to its greater space for throwing out 
side fibres of roots. From these facts I 
have no doubt that there is a side 
(lateral vascular) commvmication, both 
for absorption and exudation, from the 
heart wood, through the bark, throughout 
the whole extent of the roots, stem, 
and branches of trees ; also, that the sap 
will flow in the heart wood either up- 
wards or downwards, that is, either from 
the head towards the root, or from the 

B 2 



20 



root towards the head. I found by 
experiment, in 1832, that the roots of 
birch will bleed either upwards or down- 
wards ; and if a root of a birch is cut 
across near the stem, so that it cannot 
absorb moisture itself, it will bleed freely 
from the stem. 

These facts are at least sufficient to 
prove that the woody parts of trees im- 
bibe without the aid of the small fibres or 
ends of roots. From the following experi- 
ments, also, I am satisfied that roots do not 
imbibe at all from the small mouths (capil- 
lary stomata), or from the small sponges 
(spongioles), which are supposed to exist at 
their ends. 

In March 1836 I made some horse- 
chesnut seeds grow in water, in my barrack 
room, and found that when the root was cut 
off when it was several inches long the plant 
would still grow, and would continue to 
throw out fresh roots as fast as they were 
cut off ; but if the plant was divided from 



21 



the seed, by cutting the umbilical hands^ it 
died, though the root was perhaps twice the 
length of the plant ; yet when the seeds 
remained attached to the plants till the 
roots had become woody, the plants grew 
for years. I imagine that the elabora- 
tion of the sap is entirely in the seed, 
and passes through the umbilical bands, 
for the growth of the plant upward and 
of the root downward. These umbilical 
bands pass one to each cotyledon of the 
seed, in dycotyledonous plants. They may 
be considered as the stalks or petioles of 
leaves ; and in reference to a theory of 
Priestly's, that plants derive their nutri- 
ment from the air through the medium 
of their leaves, it may be stated that the 
cotyledons themselves may be considered 
as leaves, and indeed in many plants 
actually become what is called hypogeal, 
that is, they rise above the earth into the 
air, and are converted into what are called 
B 3 



22 



the seed-leaves ; but, I imagine, not be- 
fore the root is capable of absorbing and 
of transmitting moisture to the plant ; cer- 
tainly the cotyledons of the seeds of trees, 
full as they are of stored food, will not 
nourish their seedlings without a supply 
of water as well as air. I have known 
four cotyledons in a seed. In this case 
twin plants arise. The first side fibres 
or shoots which are developed on the 
roots of horse-chesnuts grown in water 
are regularly arranged in six vertical lines 
along the root. 

As long as the root is unripe, in other 
words, unwoody, it is wholly useless ; that 
is, it has no upward conduit for the sap. 
The small fibres of the root bear the same 
relation to a tree as children to a com- 
monwealth ; so far from being a present 
source of strength, they are an actual 
expense and outgoing, though, by their 
growth and maturity,— that is, when the 



23 

unripe fibres become woody roots, and the 
children become men, — they are the very 
springs of vital energy. 

Particular stress is laid on these doc- 
trines, because they account for the free 
growth of a transplanted tree when the 
small fibres, or ends of its roots, are all 
cut off, in contradiction to the universal 
vulgar error that trees absorb moisture 
only from the small mouths or sponges at 
the ends of their roots. If it is answered, 
that the roots of these transplanted trees, 
and the cuttings, absorb only from their 
ends which are cut, and that in the case 
of the olive branches the pillars of earth 
only prevent transpiration, I must con- 
fess that the theory is possible, but think 
the reverse most probable. . And how have 
the cuttings absorbed whose ends were out 
of the ground ? 

The upward course of the sap is through 
the whole woody part of the roots, stem, 
and branches of the tree. This woody 

B 4 



24 



part has been hitherto divided by physio- 
logists into two parts, the iieart wood or 
dead wood, and the alburnum or unripe, 
and outside rings, or latest deposits of 
wood around the stem. It was considered 
that the heart wood really was dead 
wood, and that the upward course of the 
sap was through the alburnum, or latest 
rings of wood only. In March 1832 I 
remarked the stems of some birch trees, 
which I had cut down in the previous 
November, bleeding from the heart wood. 
I was not then aware that Coulon had 
about this time observed the same thing 
in cutting down some poplar trees in 
France. I afterwards satisfied mj^self, in 
various ways, that the whole of the wood 
is the conduit for the upward course of 
the sap. 

In April 1832 I found a birch tree in 
Dyhrram Park, of from sixty to seventy 
years growth, which had a large scar 
from injuries from cart-wheels. The 



25 



scar might have existed from fifteen to 
thirty years, being perfectly indm^ated, and 
in parts turned to touchwood. I tapped 
the scar in the centre with a very large 
gimlet. I had not pierced an inch before 
it ran freely while boring. I bored about 
three inches in depth. The tree was 
about nine inches through, in the direction 
of the bore. The dead surface wood was 
perhaps a little more than a quarter of 
an inch in depth. The dropping was so 
frequent as almost to amount to a stream. 
This could only have flowed from the heart 
wood ; since no alburnum, or new wood, 
had been deposited on the scar for about 
twenty years. 

After the ascent of the sap, it is sup- 
posed to be elaborated in the leaves, and 
in descending between the wood and the 
bark, to deposit the annual ring of new 
wood or alburnum round the branches, 
stem, and roots, and also to furnish the 
new growth of the roots in length. 



26 



There is a wide difference between 
seeing and foreseeing a result. Yet when 
facts and results are shown us, how often 
do we imagine that we have foreseen them. 
I would not undervalue the magnificent 
advances of modern science ; but, cer- 
tainly, hitherto, in vegetable physiology 
and agricultural chemistry, science, far 
from directing us, has been contented 
dimly to shadow out theories to account 
for the facts and results which practice has 
ascertained. And these theories every day 
changes for new ones. Is it that a whole 
life is necessary for the acquirement of 
science, and a whole life to make practice 
perfect, and that the two weapons can 
never be wielded by one hand? That 
Liebig should reproach gardeners and 
farmers for not being chemists, is about 
as reasonable as if they were to reproach 
him for not being a gardener or a farmer. 
He who is wiser than his neighbours had 
better enlighten, not abuse their darkness. 



27 

What theorists call the prejudice of* prac- 
tical men is not so obstinate but what 
it will learn if they can teach it any thing 
to its own interest. " Physician heal thy- . 
self," The conceit of the closet can only 
be cured by practical out-door proof. 
When chemists make their fortunes as 
farmers or gardeners, farmers and gar- 
deners will follow their example. In the 
meantime those who have to do cannot 
afford to spend a life in labour, the product 
of which is a doubt. 

According to an experiment of Hales, 
which has been since verified by others, the 
sap rises with a force sufficient to support 
the pressure of a column of water of double 
the height which would burst an ordinary 
hogshead cask. And we see that it ascends 
to prodigious heights, yet we are ignorant 
how, or from w^hence, it is first absorbed, \ 
and we are ignorant of the mechanism^ 
that is, of the cause and laws, by which 
it is forced up. 



28 



We see the miraculous and universal 
system of transubstantiation with which 
we are surrounded in the vegetable world, 
yet we are not only ignorant of the 
cJiemistry which produces it, — which, from 
absorbed moisture and gases, forms all 
the various woods, bark, leaves, flowers, 
scents, fruits, seeds, &c. of that most 
exquisite kingdom, — but we are even 
ignorant in what part of the plant the 
elaboration takes place, or from what part 
of the plant the new growth is deposited. 

Whether any chemical change or elabo- 
ration of the sap really does take place in 
the leaf I shall not question ; but I think 
that possibly the leaf only gives off the 
supernumerary watery parts necessary to 
take up and conduct to their destination 
the carbonic acid, ammonia, and inorganic 
matters requisite for vegetable life, and 
that it exhales the unnecessary gases, &c. 
after the decomposition of the constituents 
absorbed from the soil. Certainly the 



29 



transpiration or giving off of water from 
tiie leaf, when exposed to drought, is very 
rapid, and the communication from the 
root to the leaf very rapid and constant ; 
since on felling trees of thirty or forty 
feet high, while they were shooting in the 
summer, I have observed the shoots lose 
their turgescence, that is, droop, in the 
course of a few minutes from the time that 
the stem is divided from the root. The 
accurate and admirable Hales found that a 
sunflower, in dry, hot, weather, gave off two 
pounds and a half, that is, two pints and a 
half of water in twelve hours. At night, 
and in moist weather, the quantity was much 
less. Senebier supposes that plants give off 
two thirds of the water which they absorb. 

Many physiologists imagine that the 
great use of the leaf is to absorb mois- 
ture. M. Bonnet tells us that the leaf 
is formed to absorb, chiefly from the 
lower part, because dew ascends. But as 
dew is a condensation of moisture sus- 



30 



peiided in the atmosphere, it cannot be 
said to ascend more than to descend ; and 
the physiologist forgets that rain descends. 
But I do not think that M. Bonnet's facts 
are more to be depended on than his 
reasoning. He states, that if leaves are 
floated on water on their upper surfaces 
they will die as soon as if they were not 
put in water, but if they are floated on 
their lower surfaces they will remain alive 
as long as if their stalks were immersed in 
water, I tried this experiment in 1836, 
and found that the leaves floated on their 
upper surfaces remained alive as long, or 
rather longer, than those on their lower 
surfaces ; one remained in part alive for 
six weeks. I have only had opportunity of 
seeing these theories of M. Bonnet quoted. 

According to this class of physiologists, 
of which the great chemist Liebig is the 
modern oracle, when trees are in full leaf 
they receive their entire nutriment through 
their leaves from the atmosphere, and "the 



31 



complete dryness of the soil would not 
then injure them. If this were so, when 
trees were cut down at Midsummer, till 
the fall of the leaf, the heads would remain 
alive, and the roots would immediately die. 
The reverse of this is the case ; the roots 
remain alive, and shoot out without any 
assistance from the atmosphere, and the 
heads immediately die. 

It is certain that great chemical changes 
or elaboration of the sap must take place 
in the root or stem before it reaches the 
leaf ; since sap of very different qualities 
is drawn from the stems of different trees. 
Witness the sugar from the maple and 
birch, the resin from the fir, &c., &c., 
which are found in the heart wood. Also 
the alteration of the heart wood in den- 
sity, and the change of alburnum into 
heart wood, argue elaboration in the stem 
and deposit from the upward sap. This 
opinion also seems to be supported by 
the fact, that when a peach is grafted 



32 



on a plum stock, &c., the new growth in 
diameter on the stock is still plum, which 
it would not be if the new crrowth was 
entirely derived from the peach leaves, or 
even if it was entirely elaborated in them, 
and entirely deposited from the downward 
sap ; while, on the other hand, if the 
elaboration was wholly in the root or 
lower stem the wood and leaves of the 
peach would become plum. But purple 
beech and variegated sycamore grow for 
ever unchano;ed, thouo:h eno^rafted on com- 
mon stocks, as a single branch of a plant 
accidentally variegated will for ever retain 
its character. This looks like local elabo- 
ration. 

I think it possible that engrafting trees 
on stocks of minor growth may incline 
them to fruit instead of growth, on the 
same principle as ringing branches or tying 
ligatures round them does. In each case 
the natural supply of sap is diminished. 

The upward growth of a tree, as com- 



33 



pared with its downward growth, may be 
said to resemble the growth of animals, by 
intus-susception ; that is, the growth of 
the shoots of the current year of the 
leader and branches is a growth or ex- 
tension of parts already formed, by the 
upward and outward increase of all those 
parts from within. Besides the growth 
at their ends, all the parts of the shoot 
of the current year, to a certain degree, 
grow bodily upwards, or by what may 
be more properly called intus-suscep- 
tion. I have observed this in plants 
which I had introduced through the 
window-sill, and trained against the 
shutter, by marking the position and 
upward progress of the stalk of each leaf 
where it joins the stem. Duhamel first 
pointed out this fact. With the excep- 
tion of the parts of the shoot of the 
current year, no other part of a tree makes 
any upward progress. 

The downward growth of a tree, that is, 
c 



34 



the elongation of the roots and the growth 
in diameter of every part of the tree, 
may by comparison be said to resemble 
the growth of minerals — by Juxta-posi- 
tlon; that is, roots are lengthened only 
by the deposit of new growth at their 
ends, and they do not progress bodily 
through the earth. I have never remarked 
accurately how this is in plants grown in 
water ; but I believe it to be the same 
as when they grow in the earth, and that 
this mode of growth is the result of the 
organic structure of the root, and not of 
the mechanical difficulty of forcing itself 
through the earth. 

It has been hitherto held that the stem, 
branches, and roots grow in diameter by 
the deposit of new growth on their out- 
side, and that there is no increase from 
within of their internal parts. 

Is it possible that the growth by intus- 
susception, or by juxta-position, may be de- 
pendent on the presence or absence of the 



35 



pith, since the roots of dycotyledonous 
plants, (plants whose seeds have two coty- 
ledons, — I know of no easier language,) 
which may be said to grow by juxta- 
position, have no pith ? In their stems and 
branches, which grow in diameter in the 
same way, the pith is supposed to be dead 
and functionless ; but in the shoot of the 
current year, which may be said to grow 
by intus-susception, the pith is a most 
prominent feature, and apparently full 
of vitality and vigour, and the woody 
monocotyledonous stem (the palm, the 
yucca, &c.), whose growth in diameter 
is entirely and permanently by intus- 
susception, may be called one entire and 
permanent column of pith. 

Duhamel thought that the last year's 
layer of bark was converted into the this 
year's layer of wood. We can see that this is 
not the case. Du Petit-Thouars thinks that 
the new layer of wood is formed by the buds 
(though I believe the origin of this theory 

c 2 



36 



is due to Darwin) ; that the fibres are the 
roots of the buds, which, at the bursting 
of the buds, run between the last year's 
bark and wood to the ends of the roots. 
Those who can assent to this theory may 
flatter themselves that they know some- 
thing of the growth of trees in diameter ; 
those who cannot believe it must confess 
their ignorance on the subject. To say 
that the new layer of wood is formed 
from the viscid substance to which Grew 
gave the name of cambium does not remove 
the difficulty. \'VTience is the cambium it- 
self formed? How and where elaborated ; 
how organised ? 

Dutrochet and Link bring us back to 
Hales' s doctrine of the all-importance of 
the pith. Indeed Dutrochet would estab- 
lish the omnipresence of the pith. He tells 
us that each division between the annual 
layers of wood is a pith for the layer 
outside it ; and that, in addition to the 
original medullary rays, which run from 



37 



the central pith to the bark, and which are 
annually prolonged through each successive 
pith and layer of wood, — in addition to 
these, intermediate medullary rays are 
developed from each new pith, which run 
from that new pith to the bark, and are 
annually prolonged. 

This growth sideways, between the 
medullary rays, is doubtless the mode in 
which alburnum is converted into heart 
wood, and heart wood increases in density. 
It must be from the upward sap ; and from 
examination of branches which have been 
rung, I have much reason to believe that 
the alburnum below the rings is thus 
converted into heart wood. This growth 
may be said to partake of the principle 
of the growth by intus-susception. One 
cannot, however, suppose that this new 
growth in the comparatively hard albur- 
num is from the roots of the buds, accord^ 
ing to Du Petit-Thouars's system. I have 
remarked, that when -firs are cut across, 

c 3 



38 



they bleed only from these rings of pith ; 
and I thi7ik I have remarked this in birch 
trees. These rings of pith are probably 
the main if not the sole conduits for the 
upward sap, which from them and the 
medullary rays exudes sideways, and^ 
through the medium of the intercellular 
passages, is possibly elaborated in the 
vessels, tracheae, and cellular tissue ; but 
probably all external paii:s of plants are 
capable of transpiration or absorption, 
according to circumstances, as well as of 
inspiration or expiration. Happily, how- 
ever, in a sketch of this sort, we are not 
called on to unravel the mass of contra- 
dictory theories 2i\\A facts of the microscopic 
observers of the vessels, cellular tissue, 
stomata, &c., of the woody layers, leaves, 
cortical layers, and epidermis. This mass 
of contradiction has been accumulating 
and entangling itself from the time of 
the admirable Grew and Henshaw, who 
originated this species of anatomical re- 



39 



search on the completion of the microscope 
by Hook, to om' own time, that is, to the 
time of the equally admirable Dutrochet. 

The medullary rays, which appear like 
the spokes of a wheel, when the stem is 
cut across, are in fact thin plates, running 
the whole length of the stem, roots, and 
branches. They are supposed by Dutro- 
chet to be of the same nature as the pith, 
though they appear very different. In 
width, they increase each year by the 
width of the new layer of wood, across 
which they extend to the bark ; and in 
length, they increase each year by the 
length of the new shoot of the branches 
and roots. 

The medullary rays and the concentric 
rings of pith form interstices in the wood, 
and prevent its perfect union. What are 
called shakes in timber arise in them. 
These shakes are often seen outside the 
stems of living oaks. They are the con- 
sequence of diseased medullary rays ; they 

c 4 



40 



proceed horizontally from the centre of the 
treej often run to a great extent vertically^ 
and are never cured. 

I think that the medullary rays may be 
seen to prolong themselves into the latest 
layers of bark if the stem of a living oak 
tree is cut across ; at least there is a white 
line across these layers opposite the end 
of each medullary ray. If these lines are 
prolongations of the medullary rays they 
probably play a prominent part in the 
deposit of the new layer of wood and 
bark ; at least these prolongations must 
of course remain for ever, and the new 
growth, both of wood and bark, must be 
deposited between them. These white 
lines across the new layers of bark may, 
however, be only organs of elaboration or 
of respiration, or conduits for absorption 
and exudation. If they are not in unison 
with the medullary rays, at least the 
commencement of each white line cor- 
responds exactly with the termination of 



41 



each medullary ray. The new medullary 
rays proceeding from the new rings of pith, 
first remarked by Dutrochet, may be easily 
seen in oaks ; they may also be seen to 
begin from the new layers deposited out- 
side the ends of dead branches. 

The root has as strong a first tendency 
downward as the stem has upward, though 
it puzzles our philosophy to account for 
either. The first downward tendency of 
the root is, however, soon counteracted by 
circumstances, such as the necessity of at- 
mospheric aeration, the goodness of upper 
compared with lower soils, the interven- 
tion of rocks, chalk, &c. ; and the root is 
found to grow horizontally, or sloping 
upward or downward, according to the 
inclination of the ground. I consider the 
idea of the tap root of the oak as a vulgar 
error. I have never seen any trace of a 
root at any great distance from the surface 
of the ground, nor do the stumps of oaks. 



42 



when grubbed, show any symptom of a 
tap root more than other trees. 

The celebrated Duhamel, wishhig to 
protect his field from robber}^ from the 
roots of a row of elms, cut a deep ditcli 
between the elms and his field. The roots, 
. however, were not to be done. They of 
course followed the surface of the ground, 
whether down, horizontal, or up hill, and 
took the ditch " in and out clever " into 
the philosopher's field. Duhamel thinks 
these were very cunning roots, and that 
they had an instinctive notion of the treat 
they were to have on the other side of 
the ditch, and grew at it. . Had the philo- 
sopher built a wall in the ditch, and then 
filled it in, he would have beaten the roots, 
on account of their inability to leave the 
surface and get under the wall. 

Were we to add one step to the beau- 
tiful theories of Knight and Dutrochet 
respecting the growth of adhesive plants, 



43 



and the tendrils of climbing plants, from 
the light, we might almost attribute the 
upright growth of the stem to the mere 
swelling (turgescence) of the cellular tissue 
of the new green shoot, and its aberration 
from the perpendicular to the effect of 
light on the swelling. 

It is asserted, on microscopic observa- 
tion, that the bark of all new green shoots 
is entirely composed of two layers of cel- 
lular tissue. The cells of the outside layer 
of tissue decrease in size from within out- 
wards ; the cells of the inside layer de- 
crease in size from without inwards. Thus 
the largest cells of each layer are next one 
another, or in the middle of the bark, and 
the smallest cells are on the two sides, that 
is, the outside and inside of the bark. 
Owing to this formation, swelling would 
stretch a slip of bark perfectly straight, 
since each layer of tissue would tend to 
curve itself outward. But in plants which 
grow towards the light the inside layer of 



44 



tissue is the thickest, and therefore tlie 
most powerful in its action, consequently 
swelling would bend a slip of such bark 
inwards or towards its shoot, and such a 
shoot would be held up by the inward 
pressure of its bark all round it, as a wall 
may be propped from both sides. But in 
the bark of plants, or parts of plants, which 
grow from the light, such as ivy, the tendrils 
of climbing plants, &c., the outside layer 
of tissue is the strongest ; and the tops 
of the shoots of such plants tend to stand 
upright by the pulling outward of their 
bark from all sides, like the mast of a 
ship. But light, by increasing the giving 
off of water (transpiration), decreases swell- 
ing, and when it falls unequally on plants, 
the forces on the illumined side will be 
weakened, and the shoot, according to the 
formation of its cellular tissue, will be 
turned either towards or from the light. 
Thus ivy, or the tendrils of climbing 
plants, are turned from the light towards 



45 



any opaque body, while the generaUty of 
plants are turned from the opaque body 
toward the hght. The whole of a plant 
kept in a room will grow towards the 
w^indow. But though this principle is not 
so striking out of doors, it is perpetual and 
universal. 

As the light falls equally on the leader 
of a tree it goes up straight. In proportion 
as it intercepts the light from above, the 
branches grow towards the light at the 
sides ; and if one outstrips its neighbours, 
the light from above turns its end up. If 
the lower tier of branches outgrows the 
tier above it, in turning up, it will take 
its neighbour with it. That tier will 
turn the tier above ; and so in succes- 
sion all the branches will grow upward. 
This growth is often seen in beech trees. 

It is this principle which prevents the 
boughs of a tree from growing against one 
another. In proportion to their opacity 
they grow one from the other. 



46 



Notwithstanding the original downward 
vertical determination of the root, and up- 
ward vertical determination of the stem, 
the annual vertical growth in elongation 
of a tree, either upward or downward, is 
nothing in comparison with the growth of 
it, which forms angles with a vertical line : 
that is, out of all the numerous points of 
elongation of the head of a tree, there is 
but one which can go vertically upward in 
continuation of the line of the stem ; and 
out of all the numerous points of elongation 
of the root, there is but one which can go 
vertically downward in continuation of 
the line of the stem ; and I believe that 
one ceases to do so very soon. 

If the leader of a tree is killed, the light 
falling equally from above on many buds 
a multiplicity of leaders may be developed ; 
though if one grows more vigorously than 
the others, by overshadowing them from 
above with its own side growth, it will force 
them to grow sideways to the light, and 



47 



the tree will again become single-leadered. 
Without pruning, a tree may become 
round-headed from the merest accident ; 
for instance, an insect, or a bird, or the 
wind destroying the top bud. A tree on 
the side of a steep hill may be seen to 
grow from the opaque side above it, and, 
after it has reached a certain height, to 
curve back again. 

So far light would appear to be the 
principal agent in directing the growth of 
plants. Yet it is said that if beans are 
planted in holes through the bottom of a 
box filled with earth, the stems will grow 
upward from the light into the earth, and 
the roots downward towards the light into 
the air ; and the plants will perish when 
they cease to derive nutriment from their 
seed-leaves or cotyledons. Nay, so deter- 
mined is the downward tendency of the 
root, that when I have inverted a newly- 
grown bean in water, so as to have the 
roots in the air, covered with a dark cup, 



48 



the existing ends of the roots, not the new 
growth, have all turned short downward 
toward the light, and that not from 
flaccidity or drooping. And even in the 
denser medium of water, if the end of a 
root is accidentally turned upward, its new 
growth will immediately turn perpendi- 
cularly downward. 

And, from an admirable experiment of 
Knight, both the ascent of the stem and 
the descent of the root would appear to 
depend on gravitation ; for when he 
subjected growing beans to a horizontal 
centrifugal force superior to gravity, their 
roots grew from, and their stems towards, 
the centre, and the whole growth of the- 
plants was horizontal. But, suppose this 
to be so : the root should obey, 

and the stem disobey, the otherwise 
universal law of gravitation, would still 
puzzle our philosophy, as I said be- 
fore. I have hitherto been unable to 
get a copy of Mr, Knight's work, and 



49 

only quote his opinions as quoted by 
others. I regret this, as, from them, 
he appears to be the most acute of all 
physiologists. 

That the growth in the girthing or 
diameter of trees is a downward growth, 
that is, from the descending sap, seems 
clear from this :— If a ring of bark is 
taken olF round the stem or branch of a 
tree, so as to intercept the return of 
the sap between the wood and the bark, 
as long as the tree or branch lives it 
will continue to increase in girthing or 
diameter above the ring, but not below 
it ; and when such a branch is sawed in 
two, lengthways, each additional annual 
layer may be counted above the ring, 
but none below it. But if the growth in 
diameter was deposited from the upward 
sap, the parts of a branch below the ring 
would be more favourably situated for it 
than the parts above the ring. 

A new innermost layer of bark (liber) 

D 



50 



is also formed each year, from the de- 
scending sap, corresponding with the in- 
creased diameter of the tree. The old or 
outward lavers are stretched outwards, 
crack, and form the rough bark seen on 
old trunks. The yearling shoot has but 
one layer of bark, the two-year old shoot 
two, and so on ; and each shoot may be 
said to have as many layers of bark, as 
well as as many laj'ers of wood, as it 
is years old. But with regard to the 
layers of bark, besides the sloughing 
off, the circumference of the earlier 
layers would be very disproportioned to 
that of the later ones. If the circum- 
ference of the bark of the seedling oak 
was half an inch, it would make a poor 
show on the outer circumference of a 
full-grown tree, supposing it to have 
existed. This growth of the bark may 
also be considered as partaking of the 
])rinciple of the growth by juxta-position, 
since the annual new laver is a distinct 



51 



coating or deposit of new growth on 
the inside of the bark, and not a growth 
or increase of parts already formed. It is 
from the downward sap, since in branches 
which are rung it ceases to be deposited 
below the rings, but is continued annually 
above the rings. 

De Candolle makes a distinction between 
the outer skin or covering of the leaf and 
annual shoot and that of all other parts 
of the tree. He calls the outer covering 
of the leaf and annual shoot the cuticle^ 
and that of the rest of the tree the epi- 
dermis. There is certainly a difference 
between living skin and bark and dead 
skin and bark, and it might be as well if 
they had different names ; but if we give 
the name of cuticle to the outer covering 
of the living bark, it will be found, with its 
green under layer of parenchyma or 
" herbaceous envelope, " to extend over a 
much larger space of our forest trees than 
De Candolle assigns to it. There is nothing 
D 2 



52 



in which even the same sort of trees differ 
more than in this respect. According to 
growth, soil, exposure, &c., the cuticle 
exists to a very indefinite period ; and it 
would be hard to say where cuticle ceased 
and epidermis began. Living external 
bark may be found on oak, ash, beech, 
Spanish and horse chesnut, sycamore, 
poplar, &c., &c., on parts varying from 
twenty to fifty years in age. On roots 
also of the same age may be found a fine 
silvery cuticle which tears off like paper ; 
though in roots, under ordinary circum- 
stances, the under layer is white, not 
green. 

De Candolle states it as a distinctive 
characteristic of roots, as compared with 
the stem, that " they do not become 
green even when they are exposed to 
the air and light." And this opinion is 
universally held by physiologists ; but it 
is an error. De Candolle, in proof of 
the opinion, states that the roots of 



53 



hyacinths grown in transparent glasses 
do not turn green. This is true of them, 
and also of the silver ends of woody roots ; 
but it must be recollected that to neither 
of these can the air be admitted when 
they grow in water, or light when they 
grow in earth. It is however, I believe, true 
of both these, under any circumstances. 
But when part of a woody root is acci- 
dentally exposed by the wearing away of 
a bank, &c., the layer below the outer 
cuticle will be found green, precisely the 
same as on a branch, though where the 
root goes under ground, both nearer and 
farther from the stem, the under layer 
will be white. The layer under the outer 
cuticle may also be observed green at the 
commencement of the root when it is 
accidentally exposed near the neck of the 
plant. This is not a matter of opinion, 
but a matter of fact, and we have only to 
use our eyes to see it. 

Each layer of bark is supposed to have 
D 3 



54 



its proper pith or cellular ring outside it. 
The green cellular or " herbaceous en- 
velope" under the outer cuticle is sup- 
posed to be the pith of the outer layer of 
bark^ and to be to the layers of bark 
what the central pith is to the layers of 
wood ; and throughout its whole extent 
there is probably a direct vascular com- 
munication between this green external 
pith of the bark and the internal central 
pith of the wood;) by means of {he medul- 
lary rays. This green parencJiymatous pith 
of the bark is in communication with and is 
in fact a continuation of the parenchymatous 
parts of the leaves, (the spongy porous 
partSj as distinguished from the woody 
fibrous parts,) as the outer cuticle of the 
stem is of the cuticle of the leaves and 
buds. 

All physiologists talk of the circulation 
of the sap ; and the expression must be 
used, though it is a very incorrect one ; 
that is, no one, I believe, has asserted, nor 



55 



can we suppose any one to imagine, that 
there is a irue circulation of the sap of 
plants, like that of the blood of animals. 
By the circulation of the sap is meant 
merely its ascent through the wood into 
the leaves and buds, thence into the green 
outer pith of the bark, on which the leaves 
and buds are situated, and its descent to 
the roots, through the rings of pith of the 
bark. How the descent dies off and stops, 
it is difficult to imagine ; but it is still 
more difficult to suppose that any part of 
the sap should re-^ascend. The whole 
affair, however, is a matter of the merest 
conjecture. And the fate of the physio- 
logist is to build theories whose very data 
are doubt and difficulty. 

The proper juices " of plants are found 
in this green " herbaceous envelope for 
example, resin in the fir ; and the woods 
of different trees do not differ more in 
their proper constituents than the barks 
of different trees ; and, possibly^ as the first 

D 4 



56 



herbaceous envelope is burst and de- 
stroyed the next ring of the pith assumes 
its functions. Indeed in the plane tree, 
whose epidermis or outer bark sloughs off 
as it dies, a green outer layer is found 
to the very foot of the largest trees, 
doubtless owing to the free admission of 
light and air. Possibly^ also^ for the deposit 
of the new external layer of wood and of 
the new internal layer of bark, it may be 
necessary to bring together, through the 
medium of the medullary rays, on the 
common ground on which the two layers 
are deposited, and on which these rays of 
the wood and of the bark meet, if not 
join, juices the product of chemical de- 
composition, assimilation, and elaboration 
in the stem from the upward sap, which 
have been subjected to respiration and 
transpiration in the leaf, and to all these 
processes in the descent of the sap through 
the bark. 

Let the practical man guard these 



57 



external piths from external injury. Be- 
sides the gnawing of horses, cattle like to 
find soft-barked trees, such as Scotch firs, 
&c., of a size that they can take between 
their horns to rub their foreheads against, 
and do infinite mischief in this way. Trees 
that are too large for this are comparatively 
safe, as the side rubbing of cattle does 
.not injure them so much; besides, that 
the dead epidermis of old trees is a great 
defence to them. 

That the growth of the root is from the 
descending sap seems clear from this, that 
if the stem of a tree is rung at any part 
between the root and the branches, so as 
to intercept the sap returning from the 
head, the tree will die, unless branches 
shoot out below the ring, whose descend- 
ing sap nourishes the root. 

In July 1832 I observed a horse-chesnut 
tree near Esher, in the corner of a field 
adjoining Sandown turnpike-gate. It had 



58 



been barked by cattle all round, I should 
suppose twenty or twenty-five years before, 
since the surface of the barked part was 
rotten, and might be picked off. Mr. King, 
steward to Mr. Spicer, to whom the tree 
belongs, said that he had recollected the 
tree in this state for eighteen years. 

The head of the tree was in full foliage, 
and at the end of some branches, which 
had been cropped by cattle the previous 
year, had shot six or seven inches. The 
girth of the barked part of the stem was 
thirteen inches and seven eighths. The 
girth below the barked part was twenty- 
two inches and a quarter, and above the 
barked part, twenty-nine inches. The 
tree had ceased to deposit new growth on 
the old scar, which I attribute to the rot- 
tenness of the surface of the scar, and to 
its having mouldered away from under the 
living bark. I think it probable that if a 
new surface was veneered over the old scar 



59 



the stem would continue to deposit new 
growth on it from above. This tree is still 
alive— 1844. 

I imagine that the reason that this tree 
has continued to live is, that each year it 
has shot out new branches from below the 
scar. These branches have each year been 
eaten off by cattle ; but they have elabo- 
rated and returned sufficient sap to nourish 
and to keep the root alive. I imagine that 
if these branches had been allowed to 
grow they would have taken so much sap 
that it would have ceased to be forced up 
the old stem, and that the old stem would 
have died. But the existence of this tree 
and of rung branches proves to ocular 
demonstration that the sap goes up the 
heart wood, since on the scar and on the 
rings no new wood or alburnum is depo- 
sited. It is true that the number of rings 
of what is called sap wood or alburnum 
differ in different trees, and even parts of 
the rings of a tree may ripen sooner into 



60 



heart wood than other parts of the same 
rings, so that on the same transverse 
section of a tree there shall be more rings 
of sap wood on one side than on the other. 
This may be observed in oaks ; but on the 
scar of this tree no alburnum or sap wood 
has been deposited for upwards of thirty 
years. 

As the roots of trees grow in length 
through the earth they are in perfect con- 
tact with it, and as they increase each 
year in girthing or diameter this contact 
is continued, and the pressure against the 
earth even increased. 1 imagine that this 
close contact of the roots with the earth 
is very essential for the absorption of 
moisture ; and that when a ball of earth 
is taken up with a transplanted tree, the 
parts of the roots contained in the ball 
are infinitely more efficient for the supply 
of sap than five times their length of root 
not in perfect contact with the earth. 
But certain it is, that, by taking a large 



61 



ball of earth, with " the tree-Hfter," I 
have transplanted trees of about twenty- 
five feet in height in every month in the 
year, without a single failure, and with- 
out the plant feeling its removal so much 
as a greenhouse plant does potting, that 
is, without a single leaf drooping, even in 
the hottest days of June, July, and August, 
though the plant was unwatered, and 
with the same growth on the tree, in the 
next and following years, as on those in 
the plantation from which it was taken. 

I consider, however, that the worst time 
to transplant a tree is when it is shooting ; 
the best time as soon as possible after it 
has shot ; that is, as soon as it has formed 
its winter bud. This will differ in dijfferent 
trees. Some are fit to transplant in June, 
or even in May. The best months for 
transplanting the generality of English 
trees with the ball of earthy are July, 
August, and September ; for though the 



62 



upward growth has then ceased, the growth 
in diameter, and the downward growth, 
that is, the elongation of the roots, is in 
the fullest tide. 

From observation of the growth of 
the root in potted plants, and also of the. 
seedlings of trees grown in water (one of 
w^hichl have in its seventh year's growth), 
I am satisfied that the great downward 
growth of the root takes place imme- 
diately after the great upward growth of 
the head ; that is, at the end of summer, 
during the autumn, and in early winter ; 
and that the wounds of the roots of trees, 
transplanted immediately after they have 
made their upward shoot, heal or cicatrize, 
or, as the gardeners say, callous over imme- 
diately. These callouses are a prolific 
source of new shoots for the root, which 
besides, from having been shortened, makes 
a profusion of lateral shoots that same 
season. These shoots become woody, and 



63 



the root is consequently in a state to 
supply the great upward demand next 
spring. 

We may convince ourselves by experi- 
ment, that the downward is after the 
upward growth of trees. If notches are 
cut on the stem of a tree from the root 
to the setting on of the first branches, 
the new growth over the scars will be 
when the tree is ceasing to shoot. The 
upper notches will heal first, in the form 
of a horseshoe, with the heels down- 
wards, that is, the growth will be on the 
upper part and the sides of the notches, 
without any growth from the lower 
parts of the notches. This fact also 
strongly corroborates the opinion that 
the new growth in diameter is from the 
downward sap ; for if it were a side 
deposit from the upward sap the lowest 
notches should heal first. I have found 
that if stems thus notched are inverted, 
the new growth comes only from the sides 



64 



of the notches, and neither from the upper 
nor lower parts of them, which I am unable 
to account for. But the notches nearest 
the head are the first to heal, and those 
nearest the root the last to heal. 

The new growth on the notches will 
be free in proportion as they are in 
the line with large branches above them ; 
and I imagine from this, that though 
the returning sap from branches deposits 
round the whole stem, it deposits most 
freely on the proper side of the 
branches ; and the larger annual deposit 
found on the outsides of the outside trees 
of plantations, which has been attributed 
by Duhamel and Buffon to their having 
their largest roots on that side, is, I have 
no doubt, the result of their having their 
largest branches on that side. An exposed 
tree standing singly will throw out its 
roots equally all round it ; but the new 
layers of wood round the stem will be 
much the largest on the leeward side. 



65 



because the largest branches are on the 
leeward side; yet if the upper part of 
one half of the side of a stem is dead^ the 
opposite living side will deposit round 
the whole living part below. And I 
imagine that it is thus that the windward 
roots of an exposed tree are nourished 
by the descending sap from its leeward 
branches. 

As far as I have remarked, though 
young roots are round, the older ones 
greatly incline to the oval shape ; and 
in all the transverse sections of roots 
which I have examined the eccentricity 
of the common point from which the 
{medullary?) rays diverge, and which is 
occasioned by the comparatively over- 
growth of the upper sides of the new 
annual rings, is very striking. May 
this be from the descending sap having 
a greater facility of depositing on the 
upper sides, or from the roots meeting 
with a less mechanical resistance from 

E 



66 



the earth on the upper sides ? The 
largest growth on branches is on the 
sides on which they have the most 
spray or small twigs ; so that branches 
which grow diagonally upward, having 
the greater quantity of spray on the out- 
side, on account of the greater quantity 
of light, will also have their annual rings 
of wood largest on the outside from the 
descending sap of the spray depositing 
most freely on its own side. 

But the stem of a tree will be ex- 
actly like a river ; its size will depend 
on the number and size of the branches 
which fall into it ; and it will be seen 
to increase below and to decrease above 
the spot where each of its branches join 
it. It is beautifully ordained, that no 
branch can grow above without depositing 
below strength to support itself. 

Fir trees, which are very regular in the 
size and position of their branches, are also 
very regular in the tapering of their stems; 



67 



but if the lower branches are cut, or killed 
by their neighbours, in the course of time 
the branchless part of the stem loses its 
tapering form. And the stem of any tree 
which has been long bare of branches shows 
like the Lower Nile, — unvarying in size, 
because without a tributary. It will appear 
to the eye as large above as below ; for 
as regards the horizontal girthing, the 
head deposits equally down the whole 
extent of the bare stem below it ; that 
is, though the over deposit of growth 
from over large branches on their own 
side of the stem may tend to make the 
stem oval instead of round, this will 
make no difference to the comparative 
horizontal girthing of the tree at dif- 
ferent heights. And if equals are an- 
nually added to unequals, though the 
original absolute inequality will for ever 
remain the same, the relative inequality 
will annually decrease ; and the stems of 
trees which have been long branchless 

E 2 



68 



may be found of nearly the same girthing 
for fifty or sixty feet in height. If the 
yearhng shoot is one inch in diameter and 
the two-year old shoot two inches in di- 
ameter, the girthing of one will be double 
that of the other; but if each shoot in- 
creases annually one inch in diameter, the 
proportion of their difference alters the 
first year ; that is, the girthing of one, 
instead of being twice as large, is only one 
third larger than the other ; and when one 
girths ten feet the other will girth ten feet 
one inch, which is in effect no difference 
at all. To grow valuable timber we should 
not only aim at a maximum height of 
branchless stem, but a maximum head on 
a maximum height of branchless stem ; for 
in proportion to the quantity of head will 
be the quantity of its downward deposit, 
or increase of the diameter of the stem. 

Against the theory of the one vernal 
ascent and the one autumnal descent of 
the sap, and in favour of the constant cir- 



69 



culation, or at least constant supply of sap, 
we must consider that boughs even of con- 
siderable thickness, cut off in the autumn, 
will become dried throughout before the 
spring. But what can account for the 
moisture of boughs, and even the most 
delicate spray, exposed at great heights in 
the air, but the constant supply of sap ? 

Indeed, if the first theory were correct, 
there is no reason why plants should not 
live through the winter out of the ground, 
and plants taken up in the autumn should 
grow as freely when again put in in the 
spring as if they had just been taken up. 
The contrary of this is the case ; the roots 
of plants taken up in the autumn, as well 
as the plants themselves, soon become 
dry. Why ? Because the roots are deprived 
of the power of imbibing moisture. 

I have observed that if the stem of 
a young tree grown in water is cut at the 
beginning of winter, the root immediately 
ceases to grow; doubtless because the atem 

E 3 



70 



is necessary to return the sap to nourish 
the root. If this theory is true, coppice- 
wood, hedges, and shrubs which are in- 
tended to shoot up again, should be cut at 
the end of winter, — not at the beginning 
of winter. If they are cut at the begin- 
ning of winter, the transpiratory parts 
of the plants in the air are dispropor- 
tioned to the absorbent parts in the earth, 
and the circulation and elaboration of the 
sap is injured through the whole winter, 
till the plant can shoot out again in the 
spring. I imagine that this circulation 
and elaboration do go on in the winter ; 
that, in the early part of winter, actual 
new growth of the root is often going 
on ; and that, during the whole of win- 
ter, the new growth is solidifying and 
becoming woody. 

I consider it a proof both of the exist- 
ence and of the necessity of this winter 
circulation and elaboration of the sap, 
that shrubs which are headed at the 



4 



71 



beginning of winter are very liable to 
break out ; they then suffer nriucli from the 
frost. When I have cut down sycamores 
in August, of about twenty years growth, 
I have known them make this unnatural 
effort to relieve their roots from suffocation; 
and I have observed the leaves on the 
shoots which they have then thrown out 
green to the middle of the succeeding 
January. Plants which do not ripen 
their wood, and which are annually killed 
in parts by frost, such as fuchsias, verbenas, 
&c., should not be cut till the frost does 
come ; they should then be cut immediately. 
This not only gives the last chance for 
the ripening of the roots, but if the plants 
are cut earlier they are very liable to 
break out, and then suffer from frost. 

I do not believe that the sap ever ceases 
to circulate ; but the tide is perhaps at 
its lowest ebb in January, and that is 
possibly the best month for felling timber. 
Timber which is felled at the high tide of 

E 4 



72 

sap and growth is extremely liable to 
fermentation and decay. 

It is a dangerous experiment to cover 
up the roots of trees. Their chief duty 
appears to be to absorb moisture in the 
soil ; but atmospheric aeration is neces- 
sary to them, and under the eternal agency 
of physical causes, acting probably on the 
peculiar structure of their cellular organi- 
sation, the roots of each tree otow at the 
level best adapted to thenijand to the offices 
which they have to perform. This should 
not be interfered with. If dressing is laid 
on the roots, it should not be deep, or of 
a nature impermeable to air. Trees which 
have had their roots deeply covered up 
languish and die, unless they throw out a 
new set of roots above the old ones which 
have been smothered ; but, generally, the 
new tier of roots is not strong enough to 
supply the exhaustion of the old head. 

Liebig tells us that the presence of 
oxygen. — consequently of atmospheric 



73 



air, — is necessary for the generation of 
carbonic acid from the humus in the soil ; 
and that from carbonic acid plants assimi- 
late their carbon (which, loosely speaking, 
the whole of the tree may be said to 
consist of), by decomposing the carbonic 
acid, and giving off the oxygen. I should 
consider this as the cause why roots keep 
within the reach of atmospheric aera- 
tion, since the main article of the food of 
trees is found in that district ; though 
Liebig follows Priestly, Senebier, and De 
Saussure in thinking that after the first 
infancy of the plant, that is, after the de- 
velopment of leaves, it is indebted to the 
atmosphere only for the supply of carbonic 
acid. But can we doubt that the chief 
growth of plants (I speak of dicotyle- 
donous forest trees) is from constituents 
absorbed from the soil, not from the 
atmosphere, when we see the perpetual 
difference of growth of the same plants in 
the different soils of the same parish ; that 



74 



is, in the same atmosphere ? The cactus 
is quoted by Liebig, Richard, &c. as thriv- 
ing on the driest soils, by deriving its 
nourishment from the air, independent of 
its root. Yet Lucas informs us, that " a 
cactus planted in a mixture of equal parts 
of charcoal and earth throve progressively, 
and attained double its former size in the 
space of a few weeks." This must have 
been from the soil, not from the atmo- 
sphere. 

Liebig supposes plants to assimilate 
their nitrogen by decomposing ammonia, 
stored in soils from rain water, manure 
and humus, and giving off the hydrogen ; 
their hydrogen by decomposing water and 
giving off the oxygen. Carbon, nitrogen, 
hydrogen, and oxygen, with certain pecu- 
liar inorganic matters absorbed from the 
soil, are the sole constituents of plants. 
Indeed all organic existences, that is, 
the endless varieties of the animal and 
vegetable kingdoms, are composed of 



75 



these four elements alone. These four 
elements are contained in carbonic acid, 
water, and ammonia. ^ Throughout all 
organic nature, during life, combina- 
tion from the constituents of these 
three goes on, and after death the de- 
composition of those combinations into 
the constituents of these three. That 
is, carbonic acid, water, and ammonia 
furnish the constituents from which, by 
combination, result all the exquisite 
living forms which we admire and love ; 
and into these three those forms are 
by decomposition eventually resolved. 
Throughout the realms of vitality the 
actual living are the late dead freshly 
combined ; and from the decomposition 
of one generation of plants and animals 
the recomposition of another generation 
results. 

I should doubt the supposed excretion 
from the roots of substances unnecessary 
to the growth of the tree. If this were 



76 

so, the roots would soon be surrounded 
with such substances, and would be in- 
capable of absorbing nutriment. In chalk 
districts eternal woods are found composed 
of nothing but beech ; in other soils, of 
nothing but oak. The oldest vineyards 
and the oldest hop-gardens are the best. 
(I say nothing of old meadows, since trees 
are in question.) In all these cases, if 
the roots excreted substances unfit for 
nourishing the plants the whole soil 
would have become saturated with them. 
Land plants grown in water are always 
unhealthv. Under these circumstances, 
may not colouring matter, or other sub- 
stances supposed to be excretion, be the 
result of disease and decay or partial 
maceration of the roots. There is no 
discoloration of the water in which the 
seedlings of forest trees al^e made to grow. 

I imagine that the roots of trees, in 
absorbing the moisture with which they 
come in contact, give off the unnecessary 



77 



parts of this by transpiration in the 
air. I do not perceive what should cause 
roots to transpire when surrounded by 
moisture, or if they do, they must return, 
like the dog to his vomit, and again absorb 
their own transpirations. 

If it were owing to the poisonous ex- 
cretions of the roots that the same crops 
cannot be taken year after year from the 
same land, this cause would apply equally 
to all lands ; but some soils are known 
which return the same crops incessantly. 

It is perhaps possible that the reason 
why each plant appears to have its 
favourite soil is, that it finds there in the 
greatest abundance the particular inor- 
ganic matters adapted to its peculiar struc- 
ture ; that the reason why particular 
plants will not grow in particular soils is, 
the absence of the particular inorganic 
matters adapted to their peculiar consti- 
tution ; and that the reason why parti- 
cular plants cease to grow on particular 



78 



lands is, their having abstracted tliose 
peculiar inorganic constituents necessary 
to them, — not their having deposited a 
suicidal poison from their roots, and thus 
forming cases of vegetable " felo de se." 

The organs of absorption of the roots 
of wheat, beans, potatoes, turnips, or 
mangel wurzel, cabbage, and lucern or 
sainfoin, probably differ as much as the 
internal and external structure of the roots 
and plants ; and, besides, searching for 
their inorganic constituents at different 
levels in the soil, they may probably be 
only capable of taking up those adapted 
to their peculiar constitution. 

In farther reference to Liebig's opinions, 
that the proper juices, the various pe- 
culiar acids, and the organic salts, found 
as carbonates in the ashes of plants, and 
formed by the combination of the alka- 
line bases, potash, soda, lime, magnesia, 
with the peculiar organic acids of plants, 
play an essential part in the functions 



79 



and development of the different parts of 
plants, cannot be doubted, though we 
are quite in the dark about it. And as 
regards the peculiar inorganic matters 
absorbed from the soil by particular plants, 
while the land is bearing one sort of crop 
it maybe lying fallow, and collecting them, 
by disintegration, for another sort. 

I believe Sir Humphry Davy first re- 
marked, on the assumption that the up- 
ward and downward growth of plants is 
vertical, that woods and crops growing on 
the side of a hill would derive no greater 
advantage from the additional space than 
if they grew on the horizontal surface of 
its base. But it must be recollected, that 
as the plants on the side of a hill rise tier 
above tier, with the same light and aeration 
from above they have a greater side light 
and aeration ; they are in fact placed head 
above head, like people in a race stand, 
where but for this arrangement the 
spectators would have good opportunity for 



80 



looking upward at the roof, but none for 
looking sideways at the race. But the 
merit of this principle is very apparent in 
the step stands^ in green-houses ; though 
probably the origin of these stands may be, 
the greater facility they give to see and to 
water the plants. But if the plants stood 
on the area of the base of the stand each 
would be shaded all round by its neigh- 
bours, and would receive light only from 
above. The base of what is called in 
Hampshire " a hanger," or a hanging 
wood, would not support as many trees 
with as full heads as stand on the hill 
side. Let us conceive these — 

Densas, umbrosa, cacumina, fagos — 

to be sunk vertically downward from their 
beautiful gradations till their roots shall 
stand on the base of the hanger ; the 
long one-sided columns of green will be 
submerged, smothered, and killed below 
the one common level of the tops, and 



81 



the plants will be deprived almos entirely 
of their organs of respiration and trans- 
piration. 

But besides this greater space for the 
heads, as the roots follow the surface of 
the earth, plants on the side of a hill have 
a greater space for their roots than if 
they had only the base of the hill side to 
grow on. In reference to an entire hill 
of a given base, this increase of surface 
or space for the roots will be not only 
directly as the height of the hill, but also 
directly as the steepness of its sides. 
Taking one side of a hill, if the side 
forms an angle of forty-five degrees with 
the horizon, its additional surface or space 
for roots, as compared with its base, 
will be as the diagonal is to the side of 
a square. 

We are not to expect that trees drawn 
up in the interior of sheltered plantations, 
and transplanted to exposed situations, 
will grow. If we could move a cube acre 

F 



82 



of ground with a young tree, from a 
sheltered to an exposed situation, the 
plant would dwindle and decay. A tree 
grown in an exposed situation contrives 
by degrees to shelter itself; that is, it 
grows to leeward of itself ; for the 
windward growth diverts the current of 
wind, and throws it up. And we see, 
in exposed trees and woods, that they 
get taller by degrees from the windward 
to the leeward side. The chief injury 
which trees suffer from wind is while 
they are shooting. If the weather is 
calm while they are shooting, they will 
make a year's growth upward, and to 
windward ; but their general growth will 
be only upward, and to leeward; not 
from being bent by the wind that way, 
but from all other growth being destroyed 
while the shoots are tender. Plenty of 
examples of this sort of growth may be 
seen in the neighbourhood of the sea. 
This is from the mechanical force acquired 



83 



by the wind in passing over *the uninter- 
rupted surface of the sea. It is common 
to attribute the blasted vegetation of trees 
in the neighbourhood of the sea to the 
sahne or chemical qualities of the sea 
breeze. If it were so, the growth would 
not be hurt more on one side of the tree 
than the other, for the atmosphere on one 
side of the tree must be as much impreg- 
nated with salt as on the other. If it were 
so, trees would grow as luxuriantly on the 
south-west side, and on the top of Mount 
Edgecombe, as they do on the sheltered 
north-east side, for the chemical qualities 
of the atmosphere must be the same in 
each place. If it were so, we should not 
find the same sort of scarecrows on our 
inland bare plains and heaths. In a 
bare open country we have only to see 
on which side of a tree is the lowest 
and shortest growth of its head to 
know where the south-west is ; and if 
the stem of such a tree is cut across, 

F 2 



84 



the largest sides of the annual rings of 
wood will be found on the north-east 
side. 

If it is attempted, by pruning out the 
leeward growth, to give exposed trees 
straight leaders, or to force them to grow 
to windward, they will decay, from want of 
head to return sufficient nourishment to 
the root ; though, if it is gradually done, 
trees may be very much helped on this 
principle. Firs, being essentially single- 
leadered trees, and not having the repro- 
ductive powers of deciduous trees, stand 
wind very badly. It is the common error 
to believe that they will stand exposure 
well, because they are found high up moun- 
tains ; but this is only where they are 
sheltered by the mountain side ; and they 
will not bear well the exposure even of our 
low bare plains, still less of the tops of very 
moderate hills. 

In the shelter of woods, from want of 
room for their roots, and from want of all 



85 



side boughs, trees in general grow weakly, 
and do not attain their maximum height 
in a minimum time, if ever. On the other 
hand, single trees, which have plenty of 
room for their roots, from exposure, or 
from the quantity of light all round them, 
generally go more to side branches than 
to height; but in sheltered situations, with 
good soils, I have no doubt that, by early 
and gradual pruning, single trees might be 
trained to much greater heights than we 
see at present. Doubtless in ornamental 
grounds every variety of growth should 
be encouraged ; and doubtless any variety 
of growth can be attained by gradually 
and constantly cutting out all growth ex- 
cept in the direction desired. To prove 
this, we have only to observe our wall 
fruit trees, and the forms of animals, 
arches, &c. into which trees are cut. In 
trees, whether for beauty or profit, no 
attribute is more to be admired or desired 
than height. In pruning to this end the 

F 3 



86 



rules are simple, and they are applicable 
alike to the nursery plant and to the 
largest timber tree. Keep a clear leader. 
Cut off' all branches large enough to 
compete with the stem, or which grow 
parallel to it. Shrive the stem up one 
third of its height. Cut all close to the 
stem. With the above exceptions, a tree 
cannot have too many branches, as the 
returning sap of each contributes to the 
growth in diameter of alt that part of the 
stem which is below it, and to the growth 
of the root both in length and diameter. 
But pruning, like thinning a plantation, 
cannot be too gradual. It should be 
annual. 

In counties where it is the practice to 
shrive the hedge-row trees, their branch- 
less stems are ascended by means of spikes 
at the sides of the feet. In the East, palms 
are ascended, to inoculate the flower and 
to gather the fruit, by placing the feet 
against the stem, and the back against a 



87 



band which encircles the stem and the 
chmber. 

A branch, as long as it is alive, does not 
form a knot in timber, but only a cross 
grain ; that is, as the stem increases each 
year in diameter it encloses each year a 
portion of the root of each of its branches, 
and the grain of these branches forms, 
of course, an angle, more or less acute, 
with the grain of the stem ; but if the 
branch dies the stem encloses each year 
a piece of dead wood instead of living 
wood, and as the bark then ceases to 
run^ very frequently the bark is enclosed 
with it. This forms a knot, instead of 
a cross grain, in the timber ; and as the 
dead wood is dry when it is enclosed, 
the living wood, when sawed up, dries 
from it. This forms a moveable knot. 
But, besides the flaw in the timber, the 
dead wood which is enclosed forms an 
impediment to the course of the sap, as 

F 4 



88 



much as if a bolt of iron was passed into 
the tree. 

De Candolle remarks, that as the 
diameter of tlie branch is at first ex- 
tremely small, but increases annually^ 
each year the stem encloses a larger 
circumference ; and that part of the branch 
which is enclosed is in the form of a cone, 
its base at the bark, and diminishing 
inward towards the pith. The outer 
part of the branch is in the form of 
a cone, its base at the bark, diminishing 
outward. This is very ingenious ; but 
no such actual internal cone exists. The 
medullary rays and longitudinal woody 
fibres of the new annual growth of the 
branch are prolonged, and run vertically 
down that part of the stem of the tree 
which is below the branch ; so that it is 
only the grain of the centre part of the 
branch which runs across the grain to the 
centre of the tree. It then runs down the 



89 



stem of the tree to the roots. The grain 
of every other year's growth annually turns 
down the stem of the tree, short of the 
centre of the tree, directly as the newness 
of its growth. The same or rather the 
reverse appearance may be observed above 
the branch if the branch and the stem 
are cut longitudinally where they join ; 
that is, the grain of each year's growth of 
the branch appears to turn up the stem 
of the tree ; for each annual downward 
growth of the branch meets the cor- 
responding annual downward growth of 
the head of the tree, joins or anasto- 
moses with it, and passes round the 
side of the branch down the stem. Thus, 
above, and below, and on the sides of the 
branch, each annual growth of the branch 
and of the stem are not two growths, but 
one growth, and it cannot be said where 
the growth of the branch ends and that of 
the stem begins ; and the part of the 
branch within the stem is much more 



90 



like the roots of a tree than a cone. 
The internal cone, so ingeniously imagined 
by De Candolle, would only exist if the 
annual downward growth in diameter of 
the branch ceased when it arrived at the 
stem. Thus a branch unduly large in 
proportion to the head of the tree will 
form from its own deposit an excrescence 
below it where it joins the stem ; and a 
dead branch, or an undersized branch, 
overgrown by the head of the tree, will 
cause a hollow below it, from stopping the 
downward current from the head, which 
cannot turn sufficiently short to deposit 
immediately below the branch. This is 
often seen in beech trees ; and the groove 
is sometimes prolonged the whole extent 
of the stem. 

When a living branch is cut off a 
vigorous tree close to the stem, new 
growth, both of wood and of bark, is gra- 
dually and annually deposited over the 
end of it. This new twin growth begins 



91 



in a semicircular form on the top and 
sides of the scar, till the growth from one 
side meets the growth from the other 
side at the lower part of the scar ; the 
growth then proceeds towards the centre 
of the circle ; and as the new annual 
growth both of wood and bark is depo- 
sited on the top as well as the sides of 
this circular wave of growth, it keeps pace 
with the level of the annually increasing 
diameter of the tree, and when the ring 
closes in the centre no indentation is left ; 
and each succeeding year the new annual 
ring of wood and of bark is deposited over 
where the branch was, with as much regu- 
larity as on any other part of the stem. 
The end of the branch will die, and dry 
to about the thickness of paper ; and a 
very slight and inconsiderable flaw will 
remain in the timber, where the living 
wood is deposited on this dead surface 
The healing takes place in like manner 
over a dead branch which is cut off. But 



92 



if a dead branch is left till it becomes 
rotten where it joins the stem, as there is 
no firm sm^ace for the deposit of new 
w^ood, a hole remains in the stem of the 
tree. In this the water, running down 
the stem, lodges, and satm^ates the parts. 
This, with the action of the oxygen of 
the air, continues the process of decay, 
which is communicated by contact to the 
heart wood of the tree. This is the fruit- 
ful source of destruction to our timber 
trees, to the life of which, otherwise, 
there is apparently no necessary limit. 
Very little care may avoid this chief cause 
of decay. 

What is called snag pruning may be 
defended so far as this,— that if the snags 
are left sufficiently long to remain alive, a 
cross grain only is continued in the in- 
creasing stem, and the diameter of this 
cross grain does not increase so much 
each year as if the head of the branch 
existed, but, owing to the overshadowing 



93 



of the head of the tree, the snags almost 
invariably die, and rot into the stem of the 
tree. 

If trees are left so close in plantations as 
to prevent the growth of all side boughs, 
or to cause the gradual death of those that 
are developed (which fills the timber with 
long dead knots), owing to the small head, 
the deposit and growth in diameter of the 
stem, and also the whole growth of the 
root, will be very slow and slight. Weak 
poles will be reared, which, when the 
plantation is thinned, will be liable to be 
blown down, or to break out all over the 
stem from the admission of light. This 
causes a severe check to the growth of the 
head, and such trees are liable to become 
stag-headed. Exposure is no excuse for 
not thinning plantations. There is no 
reason, because the heads of trees are 
exposed to wind, that their roots should be 
robbed by their neighbours, and starved 
by their own want of head. 



94 



The largest sound tree I have ever 
measured is " the grindstone oak" in the 
Holt Forest. It is thirty-five feet in 
girthing at three feet from the ground. 
It is dead, and was apparently lately dead 
when I first saw it, since the bark was 
still on it. I think it has been originally 
a pollard [polled or headed) ; and the 
largest sound timber I have ever seen in 
England has been old pollards, allowed 
to grow up in our forest grounds, after 
the pollard system had ceased. They 
were probably allowed to grow because, 
being many-headed, their timber was not 
valuable. 

The great secret of large timber is cen- 
turies of non- cutting down, good soil, room, 
and sheltered situation. These condi- 
tions rarely come together in cultivated 
countries, though they do sometimes in 
our old family places. The free growth 
and the enormous measurements of trees 
in the forests of uncultivated countries 



95 



are more frequently to be attributed to 
the concurrence of the favourable con- 
ditions above stated than to the peculiar 
attributes of the trees themselves. Such 
trees, v^hen imported, and planted on the 
poor soils and exposed situations which 
are alone planted in cultivated countries, 
make poor progress, and never reach any 
size. 

I have received the following marvel- 
lous measurements of some pinus 1am- 
bertianas on the Columbia, from an autho- 
rity that I cannot doubt. At eight feet 
from the ground they were fifteen feet in 
diameter. The stems were branchless 
to two hundred and fifty feet from the 
ground, and were there thirteen feet in 
diameter. If the new annual ring of wood 
was a quarter of an inch wide trees would 
attain this diameter in three hundred 
and sixty years ; and supposing them to 
have grown a foot a year in height, 
this would allow them eighty feet of head 



96 



above the branchless stem. That trees of 
gigantic stature are not more frequently 
found in unappropriated forests is gene- 
rally to be attributed to their want of 
room ; that is, to their growing so close as 
to injure or kill one another. They can- 
not attain to first rate growth without 
ages of contention, and killing all their 
neighbours. In doing so, the growth of 
the survivors is not only delayed for 
centuries, but in general permanently 
marred. The axe should gradually and 
successively relieve them from their 
neighbours. 

It is a great mistake of De CandoUe, 
Richard, and other French writers, to lay 
down the branchless stem as a distinctive 
characteristic of a tree. All trees which 
grow singly on sheltered lawns have 
branches down to the ground, and from 
the lowest parts of their stems ; and most 
beautiful objects they are. The branchless 
stem is the result of injury from the hand 



97 



of man, or beast, or neighbouring trees. If 
there is an exception to this rule, it is the 
Itahan pine. 

Trees which are valueless as timber, 
such as pollards, and which therefore 
escape the axe, I believe continue to exist 
for centuries, perhaps for thousands of 
years, even after they are hollow. The 
old pollards which grace our forest grounds 
and commons were probably headed as 
young trees, and their growth cut peri 
odically, as our underwood is now, the 
browsing of the deer and cattle necessi- 
tating in such places this sort of aerial 
coppice-wood. However the heads of these 
may be lopped, every year of life adds one 
ring of new wood and bark to the girthing of 
the stem. The same takes place when the 
tree is perfectly hollow. The inside dead 
wood being dry and unporous prevents 
the bleeding or efflux of the sap. I have 
found the girthing of some of these relics 
of the olden time much greater than .the 

G 



98 



girthing of any sound timber I have ever 
measured, though probably the pollards 
never girthed large as sound trees. Even 
when the circle is broken, and they stand 
like detached strips of bark, the new 
deposit of wood and bark takes place on 
their outside, while their inside is slough- 
ing or rotting off ; and these detached 
strips gradually, and annually, progress 
outwards from what was the centre of the 
tree. 

Of course, all side or lateral growth is, 
from the position of its weight, more liable 
to break than upright or vertical growth. 
When a tree takes two leaders, from want 
of light and from want of room on the 
inside, the leaders grow from one another 
to the outside, and from their weight 
inclining to the outside, without any thing 
to balance it on the inside, they are liable 
to split from one another. As each leader 
enlarges annually in diameter, the junction 
at their two bases progresses upwards, en- 



99 



closing the bark of each between the two. 
This prevents the deposit of any new wood 
on those parts of the inside of either leader, 
and consequently also prevents the perfect 
junction, or anastomosing of the wood 
of the two leaders. Besides this, water 
lodges in the hollow at the fork ; and a 
frost which is severe enough to freeze 
this water will rend apart the trunk of the 
sturdiest oak to a certainty. 

Early and constant pruning will avoid 
the cause of these fruitful sources of decay 
in timber. 

If the heads of trees are dying in, from 
accidental blight, or from the destruction 
of their leaves and shoots by a strong 
south-wester, or from frost, &c., in all 
cases they should be cut in, not only to 
where the boughs are alive, but to where 
they are vigorous, and, if possible, at the 
foot of a living twig. If the dying boughs 
are left on the tree, the sap goes up them, 
without the power of breaking out or 
G 2 



100 



returning, consequently the roots are 
starved. 

If the dying boughs are cut off. the 
sap, which would have been uselessly 
expended in them, bursts forth in the 
form of new shoots, and, in returning, 
contributes to the growth and nourish- 
ment of the roots. In such cases, trees 
are often killed by being left " to see 
where they break out." They should be 
cut immediately. Bis dat qui cito dat. 

If the branches are not cut at the foot of 
a livino; twio\ their ends should be ao;ain cut 
off at the foot of the new shoot, in order 
that its descending sap may deposit wood 
and bark over them. If long stump ends 
are allowed to remain, they rot before the 
new growth in diameter of their stock has 
enclosed and covered them. 

Near natural ponds, where the whole 
soil holds, the presence of trees is bene- 
ficial, from their prevention of evaporation, 
and from the condensation which takes 



101 



places in moist warm weather, particularly 
oil smooth barked trees ; but near artificial 
ponds or dams no growth whatever should 
be allowed. Roots are the great creators 
of leaks; nor should they be allowed on 
masonry. If stone is bored, the bore 
plugged with dry wood, and the wood 
then soaked with water (no matter by 
which end, as regards the grain, the water is 
imbibed), it will burst asunder the most 
solid rock, such is the resistless force of 
turgescence or swelling ; and this force is 
probably a main agent in raising the sap 
to the enormous heights which it attains. 
Roots act on this principle, and they will 
rend apart the strongest masonry, or lift 
any weight of stone. In Greece, Italy, and 
throughout the East, roots are the great 
dilapidators of the ruins of antiquity. We 
may observe the effect of a too sudden 
exposure to the opposite force of drought 
in the warping and rending asunder of the 
strongest woody organisations. 



102 



In the present rage for piniises, I should 
like to say a word in recommendation of 
the deodara cedar and of the araucaria 
imbricata. They are both perfectly hardy. 
The deodara is from the Himalaya moun- 
tains. It attains the largest growth, and 
is perhaps the most exquisitely graceful 
of all trees. With us its growth appears 
to be about twice as quick as the common 
cedar in the same soils. The araucaria 
is the only hardy timber tree we have of 
a really tropical character. It is from the 
Andes, and attains an enormous size. 
Like pinuses, these trees should be planted 
out early, when they are from six inches 
to a foot high. The best way to rear them 
as single trees in parks, &c., is to trench 
a pit of five feet in diameter ; to put a 
triangular fence round them of about four 
feet high, made of poles, the thinnings of 
plantations, driven into the loose ground 
so close one to the other as to prevent 
sheep browsing the plant, splayed out- 



103 



ward, bound together with bars at the top, 
and with cross bars over the top. This is 
not only hare proof and cattle proof, but 
man proof, wind proof, and frost proof ; and 
it does not give a greater degree of shelter 
to the plant than is necessary to one of 
that size. When the head of the plant 
emerges from its fence, place a single 
hexagonal post and rail round it, to 
keep off horses and cattle, but under 
which sheep can pass. It is true that 
these close fences discourage the free 
growth of the lower side branches ; but it 
must be recollected that these branches 
must eventually be taken off, on account 
of the cattle. This should be done gra- 
dually. And when the branches are out 
of the reach of sheep, the inner fence 
may be removed, and the stem bushed. 
The side branches above the inner fence 
must also be taken off by degrees. But 
the plant should not be shrived up to 
" the browsing line^^ till it is three times 



104 



as high as that Ihie. The outer fence 
may then be removed, but the stem kept 
bushed. If the side branches are taken 
off by degrees, the sap which would have 
suppKed them increases the growth and 
vigour of the remaining head ; but if 
they are too suddenly removed the plant 
will break out all over, or it will be 
starved, from want of head to elaborate 
the sap and return it to the root. With 
the exception of one at Kew Gardens, 
Dropmore, the planter's Athens, has the 
earliest araucarias planted in England, 
and I believe it has the first deodara. 

I conclude by recommending the practice 
of transplanting with the ball of earth, 
without reference to the theories with 
which it has been supported. Indeed, with 
regard to them, I do not believe that in 
all vegetable physiology or agricultural 
chemistry there is one principle to be 
depended on. In fact, the last science is 
a new light to us, for the first glimmerings 



105 

of which we are indebted to our immortal 
Davy. I say this with the deepest venera- 
tion for the brilliant talents and undaunted 
perseverance of those who have devoted 
themselves, or who still do devote them- 
selves, to sciences of the first importance 
to the existence of man and the honour 
of his Creator ; and with a heartfelt dis- 
gust at those who, pluming themselves 
on their progress in lower but more cer- 
tain science, presume to taunt with their 
want of success philosophers who have 
attempted a labour, perhaps superhuman, 
— to throw light on the hitherto impe- 
netrable darkness which has enveloped 
the processes of vitality,^ — to delineate 
the actually progressing operations of the 
hand of the Almighty in his noblest, most 
finished, most complicated works. 



H 



ADDENDUM. 



After the paragraph ending " the parts of a branch 
below the ring would be more favourably situated 
for it than the parts above the ring," page 49, 
second line from bottom, add, 

A slight deposit of new growth may be 
observed on the lower scar or lip of the 
wound of a branch which has been rung. 
This, I imagine, should be attributed to 
the descending sap already in the bark. 
And, from the same cause probably, if the 
branchless stem of a young larch tree is 
sawed across at the height of a foot from 
the ground in the spring, granulations of 
new growth, and a slight new deposit, will 
be formed around the stem, between the 
bark and the wood, during the summer. 
I at first mistook this new growth for a 
deposit from the upward sap ; but after 
the first summer the new growth around a 
stem which cannot throw out branches 
ceases, and the stem dies. The death of 

H 2 



108 



such a stem is possibly not merely the 
result of want of elaboration of the sap, 
but of want of sap to elaborate ; for the 
communication is cut off between the 
wood, the conduit of the upward sap, and 
the bark, the conduit of the downward 
sap ; and even supposing the bark without 
leaves capable of local elaboration of the 
sap, which is very probably the case, under 
the circumstances no sap would be supplied 
to the bark to elaborate. Possibly^ also, 
this is the reason why the stump ends of 
branches or stems which have been 
headed die down to the highest shoots. 
I have known a decapitated beech stem lie 
dormant for a year, that is, make this 
slight new deposit the first summer, throw 
out branches the second summer, and 
continue to live. 

The descending sap in the bark of the 
stem can, hov/ever, to a certain extent, 
ascend in the bark of the branches, and 
deposit new growth around them, as the 



109 



ascending sap in the wood can descend or 
bleed backwards. This is seen perpetually 
where branches are cut off at the distance 
of an inch or two from the stem. Their 
diameter will be enlarged each year, their 
ends cicatrised from the sap of the stem, 
and a protuberance will remain ; and this 
makes evident the unity of growth which 
must exist at the foot of each branch, even 
with the part of the stem above it. The 
distance to which the descending sap will 
ascend the descending conduits of the 
bark of another branch or stem will 
depend on the strength of the tide. The 
most remarkable case of it I ever saw is at 
Warwick Castle, on that one of the two 
magnificent cedars between the castle and 
the river which is next the mill. A branch 
of about a foot in diameter (I write from 
recollection) has been cut off at the dis- 
tance of about eighteen inches from the 
stem. The descending sap of the bark of 
the stem has ascended the whole distance on 
the upper side of this twigless and leafless 



110 



snag or stump end, and is cicatrising, or 
depositing new growth over the flat surface. 
On the lower side of the snag the new 
growth has reached only to within an inch 
or two of the end ; and in increasing the 
diameter of the branch has separated the 
bark from the wood by about an inch. I 
imagine that this snag will eventually rot, 
and occasion the death of the tree ; but 
that if it were cut off close to the stem the 
scar would be soon cicatrised over. It is a 
vulgar error to suppose that cedars will not 
bear pruning ; they will cicatrise over the 
scars from the loss of large branches more 
quickly and more surely than any other 
tree. I should have stated elsewhere that 
perhaps the best time for pruning is when 
trees are in full leaf ; they never bleed 
then. I have known sycamores and wal- 
nuts bleed when pruned at Christmas. 

But as the new growth in diameter below 
the scar of branches which have been rung 
always ceases, though the branches con- 
tinue to live, and to increase in diameter 



Ill 



above the scars, the descending sap would 
appear to be necessary to this new growth, 
if not its sole cause. And in speaking of 
the growth in diameter of the entire tree. 
I have taken this/ac/ for granted, though 
this, like most other physiological ^ac^s, is 
a possibility based on probability. 

I have observed larch poles, when nailed 
as rails in the air, without any communi- 
cation with the earth, throw out twigs the 
first summer. This would appear to be 
the result of the elaboration of the upward 
sap already in the "t^oood. 

If a piece of bark is insulated, new growth 
will be deposited from the scar of the 
continent^ but not from the island^ except 
a very slight deposit the first year from the 
descending sap already in the bark. But if 
the island has a twig or branch on it, or if 
it throws one out, which is very likely, the 
descending sap from the branch will deposit 
new growth on the scar round the island. 
We are to suppose the upward sap 



112 



from the wood of the stem passes up 
the pith and wood of the twig or new 
branch into the stalky parts of the leaves 
and buds, thence into their spongv porous 
parts, and descends thence through the 
bark of the twig to the island of bark. 
Grew shows us that the vessels (the tracheae) 
of the wood are prolonged into the woody 
fibrous or stalky parts of the leaves and 
buds. 

I have no doubt that if ever so narrow 
an isfJunus was left from the continent to 
the upper part of a branchless island, so 
as to convert the island into a peninsula, 
the isthmus would form a conduit for the 
descending sap from the continent, and 
new growth would be deposited round the 
whole scar of the isthmus and peninsula, 
as well as of the continent. 



LOKDOK : 

Printed by A. SpoxTiswoonr. 
New- Stifc-ct- Square. 



I 

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